This area of Lakeport, California was flooded due to extreme weather during the 1998 El Niño event. El Niño causes changes in rainfall patterns around the world.
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Courtesy of FEMA
El Niño and Other Climate Events
Sometimes the way the air moves around in the atmosphere changes.The way water moves through the ocean can change too. These changes can cause unusual weather for a few weeks or a few months or a year or more. Weather returns to normal when the atmosphere and ocean return to normal.
There are several different events that happen in the atmosphere and oceans. The largest are described below. These events are natural. However they might be changing because of global warming.
The El Niño-Southern Oscillation (ENSO) is the strongest of these events. It is caused by a change in the way air and ocean water moves in the tropical Pacific region. Both phases of ENSO – El Niño and La Niña – can cause changes in weather including intense rainstorms, drought, and a change in the amount of storms.
Changes in the North Atlantic Oscillation (NAO) affect winter weather in the Northern Hemisphere. The amount of snow and cold temperatures are affected by the NAO. The NAO is affected by other changes in the atmosphere like ENSO.
Last modified September 4, 2008 by Lisa Gardiner.
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